It is known to attach an apparatus to a vehicle such as a bulldozer for engaging the ground or objects, such as rocks, which are embedded in the ground. U.S. Pat. No. 3,503,456 (Larson) shows an apparatus which is attached to the rear of a bulldozer and includes a ripper which extends downwardly from the apparatus to engage rocks or other objects. U.S. Pat. No. 2,238,094 (Allin) shows a stump splitter which is attached to the bull arm of a bulldozer and extends outwardly and forwardly of a blade to engage tree stumps.
My copending application, Ser. No. 393,614, filed June 30, 1982 now U.S. Pat. No. 4,466,491, discloses a side ripper adapted to be mounted to the side of a vehicle. A ripper tip is mounted to a first arm which is pivotally attached to a second arm which in turn is pivotally attached to the vehicle. The side ripper is arranged for rotation in a plane transverse to the direction of motion of the vehicle such that embedded objects such as rocks, may be removed more easily than in the prior art. The disclosure of my prior application is hereby incorporated by reference.